fs: prevent out-of-bounds array speculation when closing a file descriptor

commit 609d544414 upstream.

Google-Bug-Id: 114199369
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Theodore Ts'o 2023-03-06 13:54:50 -05:00 committed by Greg Kroah-Hartman
parent fbe1871b56
commit eea8e4e056
1 changed files with 1 additions and 0 deletions

View File

@ -642,6 +642,7 @@ static struct file *pick_file(struct files_struct *files, unsigned fd)
if (fd >= fdt->max_fds)
return NULL;
fd = array_index_nospec(fd, fdt->max_fds);
file = fdt->fd[fd];
if (file) {
rcu_assign_pointer(fdt->fd[fd], NULL);